System and method for performing a single step cryoablation

Abstract

A system for cryoablating target tissue at a treatment site includes a cryo-element mounted at the distal end of a cryo-catheter. A balloon catheter is provided having a U-shaped balloon attached thereon. The cryo-element is threaded onto a pre-positioned guidewire and advanced within the patient's vasculature until the cryo-element is positioned at the treatment site. Next, the balloon is threaded onto the guidewire and advanced within the patient's vasculature using the balloon catheter. At the treatment site, the U-shaped balloon is interposed between the cryo-element and the target tissue. Saline solution is pumped into the balloon causing the U-shaped balloon to expand and contact both the cryo-element and the surrounding target tissue. Next, a refrigerant is expanded to cool the cryo-element, which in turn, freezes the saline solution. The resulting “ice ball” extracts heat from surrounding tissue resulting in the cryoablation of a substantially circumferential portion of tissue.

Description

FIELD OF THE INVENTION[0001]The present invention pertains generally to systems and methods for cryoablating internal tissue. More particularly, the present invention pertains to systems and methods for cryoablating conduction blocks to treat patients experiencing heart arrhythmias such as atrial fibrillation. The present invention is particularly, but not exclusively, useful for creating substantially circumferential ablations surrounding the ostium of a pulmonary vein in a single step.BACKGROUND OF THE INVENTION[0002]Atrial fibrillation is an irregular heart rhythm that adversely affects approximately 2.5 million people in the United States. Anatomically, two pairs of pulmonary veins are connected to the left atrium of the heart with each pair delivering blood to the heart from one of the patient's lungs. It is believed that at least one-third of all atrial fibrillation originate near the ostium of the pulmonary veins.[0003]It is further believed that the optimal technique to trea...

AI Technical Summary

Benefits of technology

[0015]The system can also include a mechanism for directing energy into the “ice ball” to quickly thaw the frozen “ice ball” and restore blood flow through the affected conduit (e.g. pulmonary vein). Once the “ice ball” is thawed, the saline solution can be removed f

Problems solved by technology

This often results in a non-uniform circumferential ablation that fails to form an adequate conduction block.

These structures increase the size of the distal end of the catheter, making the catheter harder to steer and navigate through the vasculature of the patient to the treatment site.

Is short, procedures requiring multiple contacts tend to be complicated, time consuming, difficult to perform, and generally unrel

Images